Montgomery County District Judge Jerry H. Hyatt, a former state legislator, was indicted by a county grand jury last night on charges of misconduct in office, obstruction of justice and conspiracy in dismissing a traffic citation issued to a woman who was a "personal and social acquaintance" and a court employe.

The grand jury also indicted the woman's roommate, Evelyn Maslar, a court clerk, on charges that she obstructed justice by making unauthorized computer entries that removed the traffic charges against Pamela Swan from the active court docket, according to Stephen Montanarelli, the Maryland special prosecutor who handled the case.

Swan, a Montgomery District Court clerical employe who was named as an unindicted coconspirator, was involved in a traffic accident July 22 and had been driving on a learner's permit without a valid license, Montanarelli said. She faced a fine of $250 for the traffic offense and was also involved in a lawsuit resulting from the accident.

The three-count indictment charges that the judge had arranged for Swan to be represented by his former law firm, King & Hyatt in Damascus, in the civil suit. Then, on Sept. 8, Hyatt appropriated the traffic case -- although it was not scheduled for his docket -- and entered a not guilty plea on behalf of Swan, the indictment charged.

Judge Hyatt then found her not guilty, without Swan appearing in court, "well knowing the act to be in violation of his trust and duties under the laws of the State of Maryland and Montgomery County," the indictment said.

Hyatt dismissed the traffic charge "full knowing" that it stemmed from the same case involving his former law firm, the indictment said.

Hyatt's attorney, Barry Helfand, who has represented the judge since Hyatt learned he was under investigation two weeks ago, issued a statement last night, saying, "Judges tell jurors every day that an indictment is just an accusation. It does not mean that the defendant is guilty . . . . This judge is not only to be presumed innocent, but is in fact innocent, and we'll prove it."

"Because he is innocent, we are going to ask for an immediate trial," said James J. Cromwell, who also represents Hyatt. "We are ready to try it Monday, Tuesday, Wednesday, as soon as the court can give us a date. It is important for the citizens of Montgomery County to preserve their confidence in judicial officers."

Hyatt, 47, a Democrat from Damascus, was elected to the Maryland House of Delegates in 1975 and represented the 15th Legislative District there for five terms until last year, when he was appointed by then Gov. Harry Hughes to the Montgomery District Court, which handles misdemeanors and traffic cases.

Maslar, 39, declined to comment last night. She said her roommate, Swan, who is in her twenties, was ill and did not wish to comment.

Hyatt and Maslar have not been arrested, but are to get summonses to appear in Montgomery County Circuit Court, Montanarelli said.

Montanarelli, whose Baltimore-based Office of State Prosecutor handles corruption cases involving public officials, said that Montgomery State's Attorney Andrew Sonner had been informed of the case from the beginning but played no substantial role. Montanarelli said the case came to his attention three months ago -- he would not say how -- and was investigated by a state police detective.

A native of Damascus, where he still lives, Hyatt received a bachelor's degree from Washington and Lee University in 1962 and a law degree from the University of Maryland School of Law in 1965. He was admitted to the Maryland Bar the same year. He served in the Army during the Vietnam War as a captain in the 1st Cavalry Division mobile air unit.

Hyatt is married and has four children, according to his attorneys.

Hyatt has been on a medical leave from the court since September, his lawyers said. He had peritonitis and was hospitalized for about a month at Johns Hopkins Hospital in Baltimore. Since then, he has been recuperating at home.